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(FILES) This June 17, 2014 file photo photo taken in Washington, DC shows bitcoin medals. Noble Markets said March 24, 2015 it is adopting Nasdaq technology for its planned Bitcoin exchange, aiming to give institutional investors a credible platform for trading the digital currency. The startup said it would implement Nasdaq's X-stream Trading technology, already used by more than 30 smaller markets worldwide, to bring the Bitcoin trade to the Wall Street mainstream from often murky fringe exchanges. AFP PHOTO / Karen BLEIER / FILESKAREN BLEIER/AFP/Getty Images